Another grand Gotham project has crumbled — with Lincoln Center last week scrapping a half-billion-dollar plan to remake the old Avery Fisher hall after two years of planning. But wealthy New York donors shouldn’t be “ashamed” of this, as patron David Geffen charged last week. Their rightful skepticism of over-ambitious schemes may have saved Lincoln Center from real disaster.

You would think that giving millions of dollars to grateful recipients is the easiest job in the world, but it’s not so simple — especially for inexperienced donors in New York.

In 2015, Geffen, the Los Angeles entertainment mogul, gave Lincoln Center $100 million to renovate its 1962 concert hall. But the project went less than harmoniously from the start.

First, the concert hall already had a name — and $15 million of the gift went to pay off the Fisher family. Heirs understandably were upset that Lincoln Center wasn’t so sentimental about ditching the Fisher Electronics founder’s memory just two decades after his death.

The already renamed “Geffen Hall,” home to the New York Philharmonic, has become a dark joke among Lincoln Center attendees, many of whom are of an age to see their own mortality and oblivion coming, statistically speaking.

Nothing is forever — but Lincoln Center management’s blithe treatment of the Fisher legacy may be a deterrent to future fund-raising.

Tension between the dead and the living, though, was the least of the project’s problems. The half-billion price tag was too optimistic for gutting the building while leaving its outside intact. The timeline, too, was risky, with The New York Times reporting construction might take more than two years.

The longer the hall must be closed for construction, the bigger the risk of a drop-off in subscribers — i.e., in regular customers the Philharmonic depends on, year after year, to take in a few concerts.

City Opera, once a mainstay of Lincoln Center, went bankrupt in 2013 in part because a year-long renovation of its own hall across the plaza from Avery Fisher left it with huge deficits.

The Philharmonic has already been losing subscribers. It took in 15 percent less revenue last year than a decade ago, after inflation. It can’t afford for people to decide they don’t miss it that much after three years away.

Similarly, many potential donors have focused on worthy causes such as charter schools rather than the arts in recent years.

It can’t help but to attract their notice that the reason for the mass-scale renovation was trumped up. Yes, the acoustics at Avery Fisher — sorry, David Geffen — Hall are bad. They have been bad for five decades. That hasn’t stopped Lincoln Center from becoming one of the world’s cultural centers.

And “bad” can have its benefits. By this point, Avery Fisher is shabby chic. One of its selling points is that it’s cheap and un-intimidating. You can see a good concert for much less than a baseball game, and you don’t have to dress any better.

And as with other recently failed grand projects — from the New York Public Library’s plan to remake its main branch into something that’s not a library to the Hudson River Park’s doomed bid to build a new island — managers and donors are so focused on the big, glamorous picture that they fail to see the little problems, the ones easier to fix.

If you’re selling a product, make it easier for people to buy it. But Lincoln Center makes life difficult for subscribers. You’ve got to plan out what you’re doing 18 months in the future, and if you turn out to be busy that night, you can’t exchange your tickets on the Web.

Casual ticket buyers are also slapped with huge fees for using the Internet. If I want two tickets to this Thursday’s performance, I have to pay another 21 percent in fees, unless I have time to go to Lincoln Center beforehand.

These obstacles deter newcomers. Why not offer no-fee tickets, since it should cost less, anyway, to sell electronically than in person? (The donor could put his name on all the tickets.)

Then, too, Lincoln Center should offer reciprocal benefits to its different groups of subscribers. Even ardent art lovers are hard-pressed to see three operas and three classical-music concerts in a season. So why not give subscriber-style discounts to people who mix and match? There are complex reasons, but they point to management and coordination, not cost, problems.

True, modest improvements are boring, and there is something noble about planning big and falling down. But why not plan for little — and be just a little more successful?

Nicole Gelinas is a contributing editor to the Manhattan Institute’s City Journal.